Shock absorbing structure

ABSTRACT

For use with an upright abutment, a belt at its ends is mounted on the abutment and has its intermediate portion disposed with the belt web vertical and cantilevered out from and spaced away from the abutment. Frangible energy absorbers are disposed between the belt and the abutment and are supported thereon. Vertical cleats reinforce the belt web. In large installations, vertical diaphragm walls or belts are used between adjacent energy absorbers. Anchor cables may pass through and engage the diaphragms or belts.

United States Patent Walker et a1.

[54] SHOCK ABSORBING STRUCTURE [72] Inventors: Grant W. Walker; Duane B.Ford;

Lester N. Meinzer, all of Sacramento; Reid S. Larsen, Fair Oaks, all ofCalif.

[73] Assignee: Dynamics Research and Manufacturing,lnc.

[22] Filed: Sept. 4, 1970 [21] Appl. No.: 69,872

[52] US. Cl ..256/1, 256/131 [51] Int. Cl. ..E0lf 15/00 [58] Field ofSearch.....256/13.1, 1; 94/1.5; 114/219;

[5 6] References Cited UNITED STATES PATENTS 2,089,929 8/1937 Brickmanet a1. ..256/13.1 1,054,510 2/1913 Crawford ..256/131 UX 1,814,6647/1931 Cahill et a1. ..256/1 1 Oct. 3, 1972 2,164,084 6/1939 Robertson..256/13.1 2,890,076 6/1959 Baechler ..256/13.1 UX

FOREIGN PATENTS OR APPLICATIONS 1,063,803 3/ 1967 Great Britain ..256/13.1 435,357 10/1967 Switzerland ..256/13.1 312,960 6/1929 Great Britain..256/13.]

Primary Examiner--Dennis L. Taylor Attorney-bothrop & West [57] ABSTRACTFor use with an upright abutment, a belt at its ends is mounted on theabutment and has its intermediate portion disposed with the belt webvertical and cantilevered out from and spaced away from the abutment.Frangible energy absorbers are disposed between the belt and theabutment and are supported thereon. Vertical cleats reinforce the beltweb. In large installations, vertical diaphragm walls or belts are usedbetween adjacent energy absorbers. Anchor cables may pass through andengage the diaphragms or belts.

1 1 Claims, 6 Drawing [Figures SHOCK ABSORBING STRUCTURE It is becomingincreasingly necessary to protect stationary structures alongsidevehicular ways or highways not only for the safety of the structuralelements themselves but likewise for the safety of the vehicles andtheir occupants in the event of collisions. In these and in othersimilar installations, the need is for an energy absorbing installationwhich is highly efiective to absorb or dissipate the forces involved inan impact and to be relatively inexpensive. It is important that thearrangement can easily be installed in the first instance and can bereplaced whenever necessary without undue labor or cost. Furthermore,the materials of the shock absorbing structure must in themselves berelatively safe and harmless and in responding to an impact must notcompound the difficulty.

It is therefore an object of the invention to provide a shock absorbingstructure, which can economically and simply be made and installed on anabutment and which can readily be maintained and replaced whennecessary.

Another object of the invention is to provide a shock absorbingstructure in which the materials involved are for the most partfrangible and do not cause any additional hazard upon impact.

Another object of the invention is to provide a shock absorbingstructure which in many instances will simply act as a fender or as abuffer to cause a carom or rebound of an impacting vehicle.

Another object of the invention is to provide a shock absorbingstructure that can withstand the customary environment, both freezingand high temperature, and which does not require any particularmaintenance over long periods of time unless impacted.

Another object of the invention is in general to improve shock absorbingdevices.

Other objects together with the foregoing are attained in theembodiments of the invention described in the accompanying descriptionand illustrated in the accompanying drawings, in which:

FIG. 1 is a cross section on a generally horizontal plane through anabutment provided with a shock absorbing structure in one form accordingto the invention;

FIG. 2 is a side elevation of the arrangement of FIG. 1, a portion beingbroken away to illustrate the interior in the cross section, thatsection being on a plane indicated by the line 2-2 of FIG. 1;

FIG. 3 is a cross section to an enlarged scale, the plane of sectionbeing indicated by the line 3--3 of FIG. 2;

FIG. 4 is a view comparable to a portion.of FIG. 1 but showing amodified version of a cleated belt included in the invention;

FIG. 5 is a plan and cross section of a device comparable to that ofFIG. 1 but showing ashock absorbing structure for installation with anenlarged abutment and under severer conditions than that of FIG. 1;

FIG. 6 is a side elevation of the structure disclosed in FIG. 5.

While it is recognized that the shock absorbing structure pursuant tothe invention can be embodied in various different environments; forexample, in docks, alongside buildings, in parking lots, for railroaduse and otherwise, it is particularly applicable to an installationalongside of or in connection with a vehicular highway from or alongsideof which there is provided an upstanding abutment 6. In FIGS. l and 2,this takes the form of a cylindrical column and can be considered to bemade of concrete such as a reinforced concrete pillar or highwaysupport.

Pursuant to the invention, there is provided a shock absorbing structureto take care of possible impacts against the abutment 6 from manydirections but particularly from the direction indicated by the arrow 7.For this purpose there is provided, as part of the shock absorbingstructure, a belt 8. This conveniently is a woven fabric belt or can bea composite structure; for example, made up of several layers such asfour layers of a polypropylene cloth with the layers, if not otherwisesecured, adhesively attached to each other by impregnation with apolyester resin. To this belt 8 there is preferably attached a pluralityof cleats 9 conveniently of a plastic material or alternatively of wood,fiber glass or light metal. The cleats have a generally semi-ovoid shapeand are secured in position in any convenient way; for example, by alayer 11 of glue or other adhesive or, in some cases, by bolts or rivetsalthough the adhesive construction is presently preferred.

While the cleats 9 can be dispensed with entirely for very light serviceor can be applied on but one side of the belt, they are preferablyapplied on the opposite sides of the belt. The cleats 12 on one side ofthe belt are arranged, preferably, directly opposite the cleats 9 on theother side of thebelt and are similarly fabricated and secured inposition.

J Either with or without the cleats, the belt 8 is secured at itsopposite ends 13 and 14 to the abutment 6 by an appropriate fasteningmeans 16 and is arranged with the belt web disposed vertically. That isexplained by indicating that the belt thickness is relatively small orthin whereas the belt width, that is, the width of the belt web isrelatively great with respect to its thickness so that when the belt isdisposed in position, as shown, its web or width extends in a generallyvertical direction. The belt in this position continues to be fairlyflexible against a horizontal force but is relatively stiff or rigidagainst a vertical force. The intermediate portion 17 of the belt istrained around the abutment 6 and is spaced therefrom to leave anintervening space 18. The belt tends to cantilever out from itsfastenings 16 and is generally self-supporting, although not necessarilyof a definite shape when viewed in plan. The vertical strength isgreatly augmented by the cleats 9 and 12, although the cleats, beingspaced'apart somewhat do not materially interfere with the generalflexibility of the belt against horizontal impact.

Disposed in the space 18 between the abutment 6 and the intermediateportion 17 of the belt web are energy absorbing structures 19substantially as shown in the copending application of Grant W. Walkeret al. entitled Energy Absorbing Device, filed May 25, 1970 with US.Ser. No. 40,220. These energy absorbing structures are arranged at somedistance above the ground with one end of an energy absorbing deviceagainst the cleats 12 or directly against the belt web and the other endagainst the abutment 6. Often, friction alone is sufficient to hold theenergy absorbers in place, although they can be fastened to the abutmentor the belt web or both but in any case are supported by the abutmentand belt web. In some instances, some of the energy absorbers 21 are notcircular cylindrical as indicated in one location in FIG. 1, but are ofa truncated, conical shape as shown in another location in FIG. 1although otherwise they are substantially the same as disclosed in thementioned copending application.

In a typical example, four such energy absorbing devices are arrangedwith their axes substantially horizontal and radial to the abutment 6and the belt 8 is relatively taut when the installation is completed.Usually the belt is spaced some distance above the ground preferably atabout the height of an automobile bumper or a major automobile bodyportion.

In operation, when a vehicle approaching in the direction of the arrow 7hits the shock absorbing structure the intermediate portion 17 of thebelt is somewhat deflected and flexed and if the impact is relativelylight and within resiliency resilinecy of the absorbers 19, very oftennothing additional occurs. On the other hand, if the impact is severethen the belt yields and permits the frangible energy absorbers 19, 21and the like to crush and transform the impact energy so that thevehicle is slowed or stopped and the abutment 6.is saved.

A similar situation transpires when the impact is not directly in thedirection of the arrow 7 but rather is at another radial direction withrespect to the abutment 6 ,or is a glancing blow to the belt itself. Inthis instance, the belt also can yield or flex and the cleats themselvesassist in transmitting the force to the other parts of the structurewith results as previously described. In cases wherein the abutment 6might be struck from any direction, such as the base of a light standardin a parking lot, the construction, instead of being approximatelysemi-circular in plan, as seen in FIG. 1, can be circula r around theabutment. I

In some instances, as shown in FIG. 4, it is preferred to make thecleats other than of a semi-ovoid shape. Instead they are made so thatat their leading edges 26 they are relatively close to the belt, whereasat their trailing edges 27 they are relatively far from the belt whenconsidered in the immediate direction of approach of a vehicle such asis indicated by the arrows 28 and 29. In this instance also, just forillustration, the cleats are installed in pairs on the belt 31 and thecleats 32 and 33 are held in place by through rivets 34. This cleatshape tends to keep the cleats from being torn off the belt and tends toprevent entanglement with projecting parts of a vehicle sliding alongthe belt or giving it a glancing blow.

Under some conditions much greater resistance to impact and much greatershock absorbing capacity is requisite. If the traffic is appropriatelychanneled, the shock absorbing structure itself takes on a directionalcharacteristic. As shown particularly in FIGS. and 6, an abutment 41 isprovided with a belt 42 secured thereto at its ends by fastenings 43.The intermediate portion 44 of the belt extends a substantial distanceahead of the abutment 41, the direction of potential impact on which isgenerally indicated by the arrow 45. In this instance the belt is spacedand supported substantially as before since there are horizontallydisposed energy absorbers 46 spaced above the ground and installed atdifferent locations.

There are also installed many other energy absorbers 47 in any selectedpattern. The numerous energy absorbers are preferably spaced apart andmaintained in position by intervening diaphragm walls 48 thatconveniently are curved substantially about the abutment 41. Thediaphragm walls can be thin sheets of suitable material or can be largesections of belt as shown in FIG. 1. In most cases, the diaphragms arepositioned and supported by a plurality of generally longitudinallyextending cables 51 and 52 that at one end are secured to the abutment41 and at the other end are connected by anchors 53 to the ground.

In the operation ofthis structure, an impact from head on in thedirection of the arrow 45 acts substantially as previously describedsince the belt portion 44 tends to distribute the impact and itself toflex and give and yield in order that, if necessary, as many as possibleof the adjacent energy absorbers 46 and 47 will come into play totranslate the energy of the impacting device into crushing ordisintegration of the energy absorbers.

Very often in this type of installation, however, the impact is not headon from the direction of the arrow 45 but may very well be a glancingblow in the direction of an arrow 54 in which instance the belt tends toflex and yield in a lateral or transverse direction partly against thediaphragm walls 48 or belts and partly against the cables 51 and 52 withthe entire structure quite possibly yielding substantially in atransverse direction and if the impact is severe enough, permitting thebelt to yield sufficiently so that the contained or surrounded energyabsorbers are fragmented. Particularly when belts are used asdiaphragms, the impact forces are distributed so that each transverserow of absorbers tends to disintegrate before the forces disintegratethe next row so that the absorbers remain in position relatively well upto the time it is their turn to disintegrate. High speed moving picturesof numerous impacts show this function clearly.

The exact shape of the shock absorbing structure can be varied from'timeto time or from installation to installation depending upon the trafficconditions, the impact to be resisted or parried, the shape or nature ofthe abutment and various other factors; but in every instance, it hasbeen found beneficial to use a somewhat flexible belt arrangedvertically on edge and acting horizontally as a cantilever so that it isvirtually selfsupporting and forms a partial enclosure at least for anumber of energy absorbers disposed-between the belt and the abutment.The maintenance or upkeep of the arrangement is relatively low and theoriginal installation is usually quite simple and economical. If animpact does shatter a number of the energy absorbers, they can readilybe replaced with the belt or belts being repositioned and in the FIGS. 5and 6 version with the cables themselves retightened if necessary. Inthe FIGS. 1 to 4 version, it is usually necessary only to replace someof the energy absorbers since the belt itself is not often badlydamaged, although if it is it can quite readily and economically bereplaced.

What is claimed is:

1. A shock absorbing structure for use with an abutment upstanding fromthe ground comprising a rela-. tively thin relatively wide belt limplyflexible when the width is horizontal and stiff when the width isvertical, means for securing the two ends of said belt to adjacentportions of said abutment with the belt width vertical and with theintermediate portion of the belt cantilevered horizontally from saidabutment out of contact with the ground and extending outwardly fromsaid abutment in at least a partial loop when seen in plan to leave asubstantial intervening space between the intermediate portion of thebelt and said abutment, and an energy transforming spacer means disposedin and extending substantially horizontally across said space and at oneend engaging said belt intermediate portion and at the other endengaging said abutment.

2. A shock absorbing structure as in claim 1 in which said spacer isfrangible.

3. A shock' absorbing structure as in claim 1 in which said belt is afabric.

A shock absorbing structure as in claim 1 including spaced apartstiffening cleats extending across the width of and united to said belt.

5. A shock absorbing structure as in claim 4 in which said cleats andsaid belt are adhesively secured together.

6. A shock absorbing structure as in claim 4 in which said cleats haveone longitudinal edge disposed near to said belt and have the otherlongitudinal edge disposed far from said belt.

7. A shock absorbing structure as in claim 4 in which said cleats aredisposed on and are united to opposite sides of said belt.

8. A shock absorbing structure as in claim 1 in which a plurality ofsaid spacers are arranged beside each other in said space betweendifferent horizontally separated parts of said belt intermediate portionand said abutment.

9. A shock absorbing structure as in claim 1 in which a plurality ofsaid spacers are arranged end to end in said space and in whichdiaphragm walls are disposed in said space between the adjacent ends ofsaid spacers.

10. A shock absorbing structure as in claim 9 in which said diaphragmwalls are curved about said abutment.

11. A shock absorbing structure as in claim 9 in which substantiallyhorizontal cables are secured at their ends and between their ends passthrough said diaphragm walls.

1. A shock absorbing structure for use with an abutment upstanding fromthe ground comprising a relatively thin relatively wide belt limplyflexible when the width is horizontal and stiff when the width isvertical, means for securing the two ends of said belt to adjacentportions of said abutment with the belt width vertical and with theintermediate portion of the belt cantilevered horizontally from saidabutment out of contact with the ground and extending outwardly fromsaid abutment in at least a partial loop when seen in plan to leave asubstantial intervening space between the intermediate portion of thebelt and said abutment, and an energy transforming spacer means disposedin and extending substantially horizontally across said space and at oneend engaging said belt intermediate portion and at the other endengaging said abutment.
 2. A shock absorbing structure as in claim 1 inwhich said spacer is frangible.
 3. A shock absorbing structure as inclaim 1 in which said belt is a fabric.
 4. A shock absorbing structureas in claim 1 including spaced apart stiffening cleats extending acrossthe width of and united to said belt.
 5. A shock absorbing structure asin claim 4 in which said cleats and said belt are adhesively securedtogether.
 6. A shock absorbing structure as in claim 4 in which saidcleats have one longitudinal edge disposed near to said belt and havethe other longitudinal edge disposed far from said belt.
 7. A shockabsorbing structure as in cLaim 4 in which said cleats are disposed onand are united to opposite sides of said belt.
 8. A shock absorbingstructure as in claim 1 in which a plurality of said spacers arearranged beside each other in said space between different horizontallyseparated parts of said belt intermediate portion and said abutment. 9.A shock absorbing structure as in claim 1 in which a plurality of saidspacers are arranged end to end in said space and in which diaphragmwalls are disposed in said space between the adjacent ends of saidspacers.
 10. A shock absorbing structure as in claim 9 in which saiddiaphragm walls are curved about said abutment.
 11. A shock absorbingstructure as in claim 9 in which substantially horizontal cables aresecured at their ends and between their ends pass through said diaphragmwalls.